Augers are well known in the art and have been employed in many industries over the years. Augers have proven particularly useful in the field of agriculture. For example augers are employed in combines, transport tube augers, and grain bins to name just a few of the many agricultural uses for augers. Examples of such agricultural augers are shown for example in U.S. Pat. No. 4,842,126 and European Patent EP 2200914.
Frequently augers are used to move fungible materials like grain from one location to another. Often times the material being moved by the augers is hard and abrasive. The hard material, for example, dried corn, is abrasive and erodes the flight of the auger. Over time, the erosion of the auger flight diminishes the flight's and thereby the auger's performance and efficiency. Such wear may cause the auger or even the equipment employing the auger to be replaced. Further, in some instances such worn auger flights can damage the very material that it intended to move.
The auger's loss of performance can be attributable to at least two types of erosion. The first type of auger erosion is found on the top edge of the flighting. In an auger application such as a transport auger such erosion creates an undesirable gap between the auger flight and the tube in which the auger turns. The increased gap allows the conveyed material to slip past the auger flight, not be moved up the tube and thereby result in decreased efficiency. The reduced efficiency of the auger system can eventually lead to the system becoming inoperable.
A second example of erosion is attributable to that which occurs along the face of the flighting. This type of erosion typically takes place along the outer periphery of the flight face and can eventually lead to large segments of flighting becoming detached from the auger.
Efforts have been made to address such auger flight erosion. For example various hard face coatings including thermal spray, plating and various heat treatments through induction or hardening have been applied to the flighting. Further efforts to address the wear problem have included the use of ultrahigh molecular weight flighting as shown in U.S. Pat. No. 4,666,033 or adding additional material to the flight face near the outer edge of the flighting. Additional material to a conveyor is shown in U.S. Pat. No. 3,937,317.
In Agricultural applications traditional weld face techniques have also been applied to augers. However, such efforts introduce a great amount of heat into the auger flight. Because the cross section of the flighting is thin, the high heat applied in this manner can distort the flighting material and further disadvantageously impart undesired metallurgical properties. Such efforts to address auger flight erosion have proven costly, labor intensive and have not reduced to the desired degree of reduced erosion and increased efficiency.